The invention concerns a device for measuring the strip tension in a metal strip, especially a steel strip, which device has a flat, level table, over which the metal strip can run and at one end of which a plurality of measuring elements is mounted, which are suitable for measuring the strip tension, where cooling elements are provided, which are installed under the table and with which cooling liquid, especially water, can be carried into the area of the measuring elements.
Devices of this general type for measuring the state of flatness, especially of a rolled strip that is under tension, are already known. A measuring roller, which is pressed against the underside of the strip, which passes over the table in a direction of conveyance, is usually used as the measuring element. The strip tension can be derived from the measured deflection of the measuring roller in the direction normal to the surface of the strip.
One also speaks of a looper or a tension meter looper in connection with devices of this general type.
Devices of the aforementioned type are described in DE 37 21 746 C2, DE 197 04 447 A1, DE 199 18 699 A1, and U.S. Pat. No. 4,004,459.
FIG. 1 shows a previously known embodiment of a device 1 of this general type for measuring strip tension. The drawing in FIG. 1 is a cross-sectional side view of the device. The metal strip (not shown) passes through the device 1 from left to right, and the strip is in contact with the upper surface of the table 2 (guide table). On the front edge 3 of the table there are a number of measuring rollers 4, which are supported by a frame 12 on a measuring sensor 14. Due to the temperature of the strip to be processed and measured, the measuring roller 4 must be cooled. For this purpose, cooling elements 5 are provided, i.e., pipelines that are supplied with water from a water source. The pipelines terminate in cooling liquid discharge orifices 9, through which the water reaches the measuring roller 4.
This previously known embodiment of a device of this type for measuring strip tension has the following disadvantages: The pipelines 5 run under the table 2 to the measuring roller 4. In this connection, the table 2 is supported on a support member (support frame) on each of its two sides or edges (as seen in the direction of strip travel). For structural reasons, a low overall height of the table is necessary in order to have sufficient room under the table for the cooling water pipes and the other components of the structure. As a result, the table is not provided with sufficient strength, and, due to mechanical and thermal stress, it can sag to such an extent that the function of the measurement system installed under the table for determining the deflection of the measuring roller is disturbed.